X-ray investigation into structural transformations in sintered magnets type Sm2(Co, Fe, Cu, Zr)17

Changes in the phase composition and coercive force of isothermally tempered sintered magnets from the Sm2(Co, Fe, Cu, Zr)12 type alloy are studied in the course of tempering at 850 deg C. It is shown that in the sintered magnets the SmCo5 type phase of non-equilibrium composition is formed at 850 deg C. The low-temperature processing leading to the coercive force growth increases the crystal lattice parameters of the SmCo5 type non-equilibrium phase, these changes being reversible. As a result of a repeated short-term hold up at 850 deg the coercive force and parameter values are reconstructed. It is assumed that such changes in the parameters testify to a reversible redistribution of elements, Cu in particular